The present invention relates to a pipe coupling.
The present invention has two co-pending applications, one of which is U.S. patent application Ser. No. 10/971,955 filed on Oct. 22, 2004. FIGS. 1 and 2 show a pipe coupling comprising a coupling member according to the invention disclosed in the one of the co-pending applications.
As illustrated in FIGS. 1 and 2, the pipe coupling 10 comprises: female and male coupling members 12, 12′ having, respectively, valve holders 26, 26′ configured to be movable within through holes 14, 14′ formed through the coupling members, in the axial directions of the through holes; and rotatable valve members 30, 30′ defining substantially spherical shapes and supported by the valve holders to be rotated about pivotal axes A, A′ extending normal to the axial directions of the through holes. When the coupling members 12, 12′ are to be connected with each other, the valve holders 26, 26′ are urged against each other to be moved rearward relative to the coupling members 12, 12′, respectively. In association with this action, the rotatable valve members 30, 30′ are rotated into their opening positions (FIG. 2) to allow a fluid to flow through the coupling members. When the coupling members are to be disconnected from each other, the valve holders 26, 26′ are pushed back under a force exerted by compression springs 28, 28′, and in association with this action, the rotatable valve members 30, 30′ are rotated into their closing positions (FIG. 1) to block the fluid and prevent it from flowing through the through holes 14, 14′ of the coupling members 12, 12′. As described above, in the pipe coupling 10, an opening/closing operation of the rotatable valve members 30, 30′ is effected under axial movement of the valve holders 26, 26′. The valve holders 26, 26′ are sealingly engaged with O-rings 24, 24′ disposed on respective interior surfaces of the coupling members 12, 12′ so that fluid is prevented from leaking to the outside of the pipe coupling through between the coupling members 12, 12′ and the valve holders 26, 26′. In the pipe coupling 10, when the female and the male coupling members 12, 12′ are disconnected from each other, respective valve holders 26, 26′ are forced by the compression springs 28, 28′ to advance forward, so that the rotatable valve members 30, 30′ are rotated to their closing positions.
In the pipe coupling 10 of the co-pending application, it is desired that when the female coupling member is disconnected from the male coupling member 12′, the valve holders 24, 24′ can be smoothly returned under force of the compression spring 28, 28′ without interference by the O-rings 24, 24′ to enable the valve members 30, 30 to be positively brought to their closing positions.